How to tell if its clear coated?

Question:Just a qns about the above question. How to tell if the plastic is treated with clear coat? I seen from other forums that uncoated plastic when scratched shows white scratches while those that are clear coat treated shows scratches same colour as the base colour. Is it true? Pls enlighten me thanks.

Answers:
hi
clear coat is scratch but not below the paint surface will show light color and if you wet it it will change to the original color
if below the clear coat, it will turn white under